First, sorry for my bad English, I'm French. For some time, I have this problem and I do not know what it is.
There are irregularities in the first layers. I have Anet A8 and I print with PLA (Sunlu).
Here are some photos.
Thank you in advance for your help.

This looks like you might be printing too close to your build surface. I would suggest re-leveling your bed or using a positive G-code offset of ~.05 in the Z direction. This setting is found in the Gcode tab under the Global Gcode Offsets heading.